题目内容
一个正方体的表面涂满了颜色,按如图所示将它切成27个大小相等的小立方块,设其中仅有i个面(i=1,2,3)涂有颜色的小立方块的个数为xi ,则x1, x2 , x3之间的关系为
[ ]
A.x1-x2 + x3 = 1
B.x1+ x2-x3 = 1
C.x1 + x2-x3 = 2
D.x1-x2 + x3 = 2
B.x1+ x2-x3 = 1
C.x1 + x2-x3 = 2
D.x1-x2 + x3 = 2
D
练习册系列答案
相关题目